[PATCH 2/2] xfs: ensure that single-owner file blocks are not owned by others

Darrick J. Wong
2022-12-30T22:44:54Z

For any file fork mapping that can only have a single owner, make sure
that there are no other rmap owners for that mapping. This patch
requires the more detailed checking provided by xfs_rmap_count_owners so
that we can know how many rmap records for a given range of space had a
matching owner, how many had a non-matching owner, and how many
conflicted with the records that have a matching owner.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/scrub/bmap.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c
index abc2da0b1824..b195bc0e09a4 100644
--- a/fs/xfs/scrub/bmap.c
+++ b/fs/xfs/scrub/bmap.c
@@ -308,6 +308,7 @@ xchk_bmap_iextent_xref(
struct xchk_bmap_info *info,
struct xfs_bmbt_irec *irec)
{
+ struct xfs_owner_info oinfo;
struct xfs_mount *mp = info->sc->mp;
xfs_agnumber_t agno;
xfs_agblock_t agbno;
@@ -328,19 +329,30 @@ xchk_bmap_iextent_xref(
xchk_bmap_xref_rmap(info, irec, agbno);
switch (info->whichfork) {
case XFS_DATA_FORK:
- if (!xfs_is_reflink_inode(info->sc->ip))
+ if (!xfs_is_reflink_inode(info->sc->ip)) {
+ xfs_rmap_ino_owner(&oinfo, info->sc->ip->i_ino,
+ info->whichfork, irec->br_startoff);
+ xchk_xref_is_only_owned_by(info->sc, agbno,
+ irec->br_blockcount, &oinfo);
xchk_xref_is_not_shared(info->sc, agbno,
irec->br_blockcount);
+ }
xchk_xref_is_not_cow_staging(info->sc, agbno,
irec->br_blockcount);
break;
case XFS_ATTR_FORK:
+ xfs_rmap_ino_owner(&oinfo, info->sc->ip->i_ino,
+ info->whichfork, irec->br_startoff);
+ xchk_xref_is_only_owned_by(info->sc, agbno, irec->br_blockcount,
+ &oinfo);
xchk_xref_is_not_shared(info->sc, agbno,
irec->br_blockcount);
xchk_xref_is_not_cow_staging(info->sc, agbno,
irec->br_blockcount);
break;
case XFS_COW_FORK:
+ xchk_xref_is_only_owned_by(info->sc, agbno, irec->br_blockcount,
+ &XFS_RMAP_OINFO_COW);
xchk_xref_is_cow_staging(info->sc, agbno,
irec->br_blockcount);
xchk_xref_is_not_shared(info->sc, agbno,